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Real Analysis: Cardinality and Countability

Show that all even numbers are countable by mapping them onto the set of natural numbers.

Show that the set {112\frac{1}{1^2}, 122\frac{1}{2^2}, 132\frac{1}{3^2}, ...} is countable by creating a bijection to the natural numbers.

Prove that the set of all real numbers between 0 and 1 is uncountable.

Determine whether a given set is countable by demonstrating a one-to-one correspondence with the positive integers.

Prove that the set of all rational numbers between 0 and 1 is countable.

Identify examples of uncountable sets within continuous subsets of the real line.

Given an output value in a one-to-one correspondence between natural numbers and even integers, determine the input value.

Prove that the cardinality of the natural numbers, denoted as 0\aleph_0, is equal to the cardinality of the set of all positive odd integers.

Prove that the set of rational numbers Q\mathbb{Q} is countable by using the classical method of defining the height of a rational number and showing it as a countable union of finite sets.

Using Campbell's method with base 11, prove that the set of positive rational numbers Q+\mathbb{Q}^+ is countable.

Establish a bijective correspondence between the integers and the rational numbers.

Prove that the set of real numbers between 0 and 1, where their decimal expansion only contains the digits 3 and 4, is uncountable using Cantor's diagonalization argument.

Prove Cantor's Theorem which states that for any set AA, the power set of AA always has a cardinality strictly greater than AA.